Kaolin is a widely used clay for cosmetic purposes. It won't swell or thicken in water like bentonite clay does so it does require suspending in a water-based product using either a thickening gel agent or an emulsifier. Kaolin is commonly used as the base for clay masks where it provides good coverage and drying capacity. It it common to use Kaolin as a base clay and then add specialist, more active clays over the top of this to provide the activity.
Use Levels: 0.5-50% Typically but can be applied to the skin in any concentration once wetted.